Ventilating fan



Oct. 16, 1951 M 2,571,374

VENTILATING FAN Filed June 21, 1948 a INVENTOR.

Aomaeerl'. M4 m MAM Patented Oct. 16, 1951 VENTILATING FAN Adalbert I. Mayr, Milwaukee, Wis., assignor to Theresa Mayr, Kiel, Wis., as trustee Application June .21, 1948, Serial No. 34,180

8 Claims. 1

This invention relates to improvements in ventilating fans, and more particularly to a novel ventilating fan equipped with a reaction perated shutter.

An object of the invention is to provide a device of the type havin a shutter operated by mechanical means, utilizing the reaction of the fan motor as a source of energy continuously as long as the motor is energized.

Another object of the invention is to eliminate the auxiliary motors or solenoids found in devices of the type now in use for actuating ventilating fan shutters.

Other objects of the invention will be apparent as the description proceeds, reference being had to the accompanying drawing, in which:

Fig. 1 is a rear view through the casing, showing the fan, motor and shutter opening mechanism.

Fig. 2 is a side view partly in elevation and partly in section of the device.

Fig. 3 is a side view partly in section and partly in elevation showing a detail of the shutter mechanism.

Fig. 4 is a vertical sectional view showing the motor suspension.

Fig. 5 is a view in elevation of the slip ring brushes.

Fig. 6 is a view in elevation of the slip rings employed.

Referring more particularly to the drawings, a building structure I0 is apertured at II to receive the ventilator casing I2 having the grill l3 and the shutter I4 pivotally hun at I5 thereof. The shutter I4 has a lever arm I6 ailixed thereto at IT thereof and connected by a coil spring I8 to a pull cord or chain I9. An electric motor 20 has a conventional drive shaft 2| and the fan 22. The ventilator casing I2 is provided with a pair brackets 23 disposed at top and bottom interiorly thereof. The brackets 23 secure by means of bolts 24, the frontal frame member 25 and the rear frame member 26, the motor 26 is provided with the front trunnion bracket 26a and the rear trunnion bracket 21 affixed thereto by rivet or threaded means 28. The front trunnion bracket 26a is secured to the hollow spindle 29 which freely surrounds the drive shaft 2| and is threaded at 30 to receive a retainer ring 3i. The Spindle 29 is rotatably held in the aperture at 32 of the front frame 25. The rear trunnion bracket 21 has disposed exteriorly thereof the slip ring plate 33 provided with the concentrical slip rings 34 and 35, and the rearwardly projecting spindle 36 which latter 2 ha v its outer end the reel 31. The spindle 36 is journaled in the aperture at 38 of the rear fram member 26, The frame member 26 has affixed thereto by threaded or other means 39 the plate 40 which supports the slip ring brushes '4l and 42 which latter are connected to the electrical conduit 43. It will be seen that the spindle 36 turns with the motor 20, as does the spindle 29. A coil spring 45 normally maintains the shutter I4 in closed position against the ventilator casing I2. The pull cord or chain I9 is led over the pulley 46 and pulley 41 is wound about the reel 31.

In use, when the motor 20 is energized, the shaft 2| and fan 22 will turn in a normal manner. The motor 20 being mounted as it is on the trunnion brackets 26a and 21 for free rotation in the frame members 25 and 26, will move with a tortional reaction in a direction opposite to that taken by the fan 22, with the result that the cord I9 will be wound upon the reel 31 until the shutter I4 is raised against the ten sion of spring 45 to the limit of its rise. The action of the cord or chain l9 at this point will be to brake the reactional rotation of the motor 20, thus holdin it against further rotation. When the motor 20 is de-energized, the action of spring 45 will unwind the cord I9 and close the shutter I4.

It will be understood that the device is capable of various modifications in structure and design, without departing from the spirit of the invention, within the scope of the appended claims.

Having thus described the invention, what is claimed and desired to be secured by Letters Patent of the United States, is:

l. A ventilating fan assembly comprising an electric motor mounted for coaxial rotation with its rotor, a fan on said rotor, a reel fixed to said motor, a fan shutter, and a pull chain windable on said reel and connected to said shutter whereby when said motor is energized the torsional reaction thereof will wind the chain on said reel and open said shutter.

2. In an electric motor, a rotor, a fan on said rotor, suspension means for said motor rotative coaxially with said rotor, a reel fixed to the motor, a fan shutter, and means windable on said reel by torsional reaction of the motor when the latter is energized to actuate said shutter.

3. A ventilating fan assembly comprising a casing, a frame fixed in said casing, an electric motor journaled in said frame for free coaxial rotation with its rotor, a fan on said rotor, a reel fixed to said motor, a fan shutter on said casing, and

means connected to said shutter and windable on said reel by torsional reaction of said motor when the latter is energized.

4. A ventilating fan assembly comprising a casing, a frame fixed in said casing, an electric motor journaled in said frame for free coaxial rotation with its rotor, a fan on said rotor, a reel fixedto said motor, a fan shutter on said casing, means connected to said shutter and windable on said reel by torsional reaction of said motor when the latter is energized, and spring means for return of said shutter to closed position when said motor is de-energized.

5. A ventilating fan assembly comprising, a motor having a rotor and a field rotatable in opposite directions, a fan operable by said rotor,

a flow control shutter for said fan, means operable by rotary motion of said field to operate said shutter, and means for closing said shutter when said fan stops.

6. A ventilating assembly comprising, a motor having a rotor and a rotor support rotatable in opposite directions, a fan rotatable by said rotor, a fan shutter disposed in the path of air flow induced by the rotating fan, a connection between said support and said shutter for causing the torque of said motor to open the shutter,

4 and means for automatically closing said shutter when said fan stops.

7. A ventilating assembly comprising, a motor having a rotor and a rotor support rotatable in opposite directions, a fan rotatable by said rotor, a fan shutter disposed in the path of air flow induced by the rotating fan, mechanism operable by the torsional rotation of said support for opening said shutter, and means operable to close said shutter whenever said motor stops.

8. A ventilating assembly comprising, a motor having a rotary armature and a field movable by torque set up in the armature, a fan rotatable by said armature, a fan shutter, mechanism connecting said field and said shutter and being operable by said torque to open said shutter, and means for closing the shutter when the fan stops.

ADALBERT I. MAYR.

Name Date Persons June 7, 1932 Number 

